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Study: Two million deaths worldwide linked to air pollution

Particulate
matter, tiny grains that are thrown into the air by construction or
vehicle speeding on gravel roads, poses a very real health risk. A new
study has linked at least two million deaths to air pollution alone,
particulate matter in particular.

LOS ANGELES, CA (Catholic Online) - Particle pollution has been linked with early death from heart and lung diseases, including lung cancer. Dense concentrations of particulate matter have been increasing due to human activities.

Ozone, which forms when pollutants from sources such as automobiles or factories come together and react were also linked to 470,000 deaths annually. Exposure to ozone has been linked to death from respiratory diseases.

The majority of the fatalities linked to air pollution are in East and South Asia, which have large populations and severe air pollution.

"Air pollution is an important problem," study researcher Jason West, an assistant professor of environmental sciences at the University of North Carolina says. "It's probably one of the most important environmental risk factors for health." The study suggests that improving air quality around the world would increase life expectancy for some, West says.

While some researchers have suggested that climate change can make air pollution more deadly, the new study found that climate change had only a small effect on air pollution-related deaths.

The way unhealthful air and climate mixes takes different forms. Climate-related factors such as temperature and humidity can affect the reaction rates of particles in the air, which in turn determine the formation of pollutants. Rainfall - thought to rid the atmosphere of smog and bad air can affect accumulation of pollutants, the researchers said.

Changes in climate were linked with just 1,500 yearly deaths from ozone pollution, and 2,200 yearly deaths from fine particulate matter, researchers said.

Scientists also used a number of climate models to estimate concentrations of air pollution around the world, in the years 1850 and 2000. Focusing on these two years allowed the researchers to determine what proportion of air pollution was human-caused, attributed to factories and gas-powered vehicles.

Researchers then used information from past studies on air pollution and health to determine how many deaths are linked with particular concentrations of air pollution, West said.

The scientists inject a note of caution: Most of the studies on air pollution and health were conducted in the United States. Applying those results globally, as the current study did, introduces some uncertainty.